1. Field of the Invention
The invention assumes a method for insulating glass panes from two or more than two glass sheets. Such a method and such a device are known from the EP 0 539 407 B1
2. Description of the Related Art
The EP 0 539 407 B1 reveals a press, in which glass sheets are assembled and pressed to a specified thickness between a fixed pressing plate and a plate parallel to this, whose distance can be adjusted, to make insulation glass panes.
In the known press, both the pressing plates are not exactly vertical, but instead are inclined by a few degrees. In the press, two glass sheets, from which an insulation glass pane is to be made, are positioned lying opposite to each other. One of the glass sheets is equipped with a frame-like spacer and lies at the pressing plate inclined backward, while it stands on a horizontal conveyor. The other glass sheet is held opposite to this at the other, movable pressing plate, especially by the mechanism of sucking it to the movable pressing plate. When the movable pressing plate approaches the fixed one, this glass sheet gets stuck to the spacer holding the glass sheet lying opposite, as a result of which the insulation glass pane is closed.
Before the insulating glass pane is completely closed, it can be filled in the press with a heavy gas. For this purpose a section of the movable press plate, which lies backward at one of the protruding margins of the pressing plate, that is, away from the opposite pressing plate, can be bent. The sucked glass sheet is thereby also bent backward. If the movable pressing plate is now brought near the fixed pressing plate in this state, then the insulating glass pane is closed except in the area, in which one of the glass sheets is bent backward. In the almost completely closed insulating glass pane, heavy gas can be introduced through the gap between the bent glass sheet and the spacer, which displaces air from the insulating glass pane. Thereafter the insulating glass pane is closed completely by cancelling the bend in the pressing plate and in the glass sheet attached to it.
Presses, in which the insulating glass panes can be assembled and filled with gas, frequently have a length of 3.5 m. However, it is possible that the insulating glass panes are longer than the pressing plates. Insulating glass panes with a length of up to 5 m are frequent. They can be assembled and filled with gas in the presses known from the EP 0 539 407 B1. To do this, one positions the glass sheets in the press in such a way that they close flush with that margin of the movable press plate, at which the section bent backward is provided. At the opposite end of the press plates the glass sheets then protrude beyond this. Too long glass sheets can, therefore, be assembled and filled with gas in the known press, because when the movable press plate approaches the fixed press plate, even the protruding section of the insulating glass pane is closed and the heavy gas can be filled, as usual, at the opposite bent end.
In case of especially long insulating glass panes, however, it is difficult to displace the air from the far-reaching areas at the other end of the insulating glass pane with the heavy gas, which is introduced at the bent end of the insulating glass pane. Presses, in which the insulating glass pane is filled with heavy gas at the lower end, avoid this disadvantage. For instance, such a press is known from the EP 0 674 086 B1 and from the EP 0 674 087 B1. In it, the glass sheets being assembled to make insulating glass panes can also be placed parallel and unconnected to each other. The heavy gas is introduced via the openings in a conveyor belt, on which the glass sheets are present, as long as the glass sheets are still completely unconnected. To ensure that the heavy gas does not flow out of the area between the glass sheets, adjustable sealing elements, running, from bottom to top, are provided, which become effective at the protruding ends of the glass sheets. In the area thus formed between the glass sheets and the sealing elements, the heavy gas now rises from bottom to top and displaces the lighter air to the top.
Alternatively, the glass sheets, of which one is carrying a spacer, can also be arranged in such a way in the presses known from the EP 0 674 086 B1 and the EP 0 674 087 B1, that the other glass sheet with its upper margin also lies against the spacer, so that the glass sheets diverge away from each other in a wedge-shaped manner from top to bottom. Even in this case, the area between the glass sheets is filled with heavy gas from below, which displaces the air above through a free area between the sealing elements and the protruding margins of the glass sheets or between the sealing element and the protruding side piece of the spacer.
If the heavy gas has risen till the upper margin of the glass sheets, the movable press plate is brought closer to the stationary press plate and thereby the insulating glass pane is closed and pressed.
In such a press excessively long insulating glass panes can be assembled, but cannot be filled with a heavy gas, because the section of the still unconnected glass sheets, protruding out of the press, would still be open, from which the heavy gas would flow out unrestricted.